/Engine/Source/Editor/KismetCompiler/Public/KismetCompilerMisc.h
For example, if a parameter in SourceFunction is of type float, but its corresponding type in OtherFunction is double, then the function is deemed "convertible". This is primarily used for binding Blueprint functions with native delegate signatures that use float types.
static ConvertibleSignatureMatchResult DoSignaturesHaveConvertibleFloatTypes ( const [UFunction](API\Runtime\CoreUObject\UObject\UFunction) * SourceFunction, const [UFunction](API\Runtime\CoreUObject\UObject\UFunction) * OtherFunction )